About us
We are a theoretical research group at the School of Electrical and Electronic Engineering and the Institute for Digital Molecular Analytics and Science at Nanyang Technological University, Singapore. The group is lead by Assistant Professor Matthew R. Foreman.
Our research focuses on optical and plasmonic sensing, polarisation sensitive imaging, disordered media and electromagnetic theory. More information on some of our past and present projects can be found by visiting our Research pages.
Recent news
New Research Fellow - Radhikar Nair
11 Mar 2024: We are excited to announce Radhika Nair as its newest Research Fellow. Radhika brings a strong background in SERS-based sensing, 2D materials, and plasmonic nanoparticles, all of which will be instrumental to the team's ongoing research endeavors at IDMxS.
New PhD Student - Jennifer Tanadi
15 Jan 2024: It is wonderful to be able to welcome our latest group member, Jennifer Tanadi, who is joining as a PhD candidate. Jennifer graduated with her BEng from the National University of Singapore and has since been working at the Institute of High-Performance Computing (A*STAR) simulating nanostructures and silicon photonic devices. Her project will consider modelling of nanoplasmonic and photonic systems for sensing applications within the fold of IDMxS.
New Research Fellow position available - Apply now!
14 Jan 2024: We have a new opening for a Research Fellow at the Insitute for Digital Molecular Analytics and Science (IDMxS). The position will focus on analysing nanoparticles and biomolecules through polarisation engineering (see here for details and to apply). Applications should be made via the NTU Workday portal. Feel free to get in touch if you have questions.
Recent publications
Abstract : In this work we present a method for generating random matrices describing electromagnetic scattering from disordered media containing dielectric particles with prescribed single particle scattering characteristics. Resulting scattering matrices automatically satisfy the physical constraints of unitarity, reciprocity and time reversal, whilst also incorporating the polarization properties of electromagnetic waves and scattering anisotropy. Our technique therefore enables statistical study of a variety of polarization phenomena, including depolarization rates and polarization-dependent scattering by chiral particles. In this vein, we perform numerical simulations for media containing isotropic and chiral spherical particles of different sizes for thicknesses ranging from the single to multiple scattering regime and discuss our results, drawing comparisons to established theory.
Abstract : We report sensing of single nanoparticles using disordered metallic nanoisland substrates supporting surface plasmon polaritons (SPPs). Speckle patterns arising from leakage radiation of elastically scattered SPPs provides a unique fingerprint of the scattering microstructure at the sensor surface. Experimental measurements of the speckle decorrelation are presented and shown to enable detection of sorption of individual gold nanoparticles and polystyrene beads. Our approach is verified through bright-field and fluorescence imaging of particles adhering to the nanoisland substrate.
Abstract : We study the polarisation properties of random N×N scattering matrices distributed according to the circular orthogonal ensemble. We interpret 2×2 sub-blocks of the scattering matrix as Jones matrices and study their statistical properties. Using the polar decomposition, we derive probability density functions for retardance and diattenuation from scattering matrices of arbitrary size and in the limit N → ∞.
Funding
Our research is supported by generous funding from:
